title: Dual origins of functionally distinct O-LM interneurons revealed by differential 5-HT(3A)R expression.
abstract: Forebrain circuits rely upon a relatively small but remarkably diverse population of GABAergic interneurons to bind and entrain large principal cell assemblies for network synchronization and rhythmogenesis. Despite the high degree of heterogeneity across cortical interneurons, members of a given subtype typically exhibit homogeneous developmental origins, neuromodulatory response profiles, morphological characteristics, neurochemical signatures and electrical features. Here we report a surprising divergence among hippocampal oriens-lacunosum moleculare (O-LM) projecting interneurons that have hitherto been considered a homogeneous cell population. Combined immunocytochemical, anatomical and electrophysiological interrogation of Htr3a-GFP and Nkx2-1-cre:RCE mice revealed that O-LM cells parse into a caudal ganglionic eminence-derived subpopulation expressing 5-HT(3A) receptors (5-HT(3A)Rs) and a medial ganglionic eminence-derived subpopulation lacking 5-HT(3A)Rs. These two cohorts differentially participate in network oscillations, with 5-HT(3A)R-containing O-LM cell recruitment dictated by serotonergic tone. Thus, members of a seemingly uniform interneuron population can exhibit unique circuit functions and neuromodulatory properties dictated by disparate developmental origins.
authors.affiliation: 1] Program in Developmental Neurobiology, Eunice Kennedy-Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, Maryland, USA. [2].
authors.forename: Ramesh
authors.initials: R
authors.lastname: Chittajallu
authors.forename: Michael T
authors.initials: MT
authors.lastname: Craig
authors.forename: Ashley
authors.initials: A
authors.lastname: McFarland
authors.forename: Xiaoqing
authors.initials: X
authors.lastname: Yuan
authors.forename: Scott
authors.initials: S
authors.lastname: Gerfen
authors.forename: Ludovic
authors.initials: L
authors.lastname: Tricoire
authors.forename: Brian
authors.initials: B
authors.lastname: Erkkila
authors.forename: Sean C
authors.initials: SC
authors.lastname: Barron
authors.forename: Carla M
authors.initials: CM
authors.lastname: Lopez
authors.forename: Barry J
authors.initials: BJ
authors.lastname: Liang
authors.forename: Brian W
authors.initials: BW
authors.lastname: Jeffries
authors.forename: Kenneth A
authors.initials: KA
authors.lastname: Pelkey
authors.forename: Chris J
authors.initials: CJ
authors.lastname: McBain
mesh_terms: D000200:Action Potentials / Q000235:genetics / Q000502:physiology; D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000378:metabolism; D002465:Cell Movement / Q000235:genetics; D002766:Cholecystokinin / Q000378:metabolism; D004622:Embryo, Mammalian; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D006624:Hippocampus / Q000166:cytology* / Q000502:physiology*; D066298:In Vitro Techniques; D007395:Interneurons / Q000187:drug effects / Q000378:metabolism*; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008239:Lysine / Q000031:analogs & derivatives / Q000378:metabolism; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D009434:Neural Pathways / Q000187:drug effects / Q000378:metabolism; D018377:Neurotransmitter Agents / Q000494:pharmacology; D009687:Nuclear Proteins / Q000235:genetics; D044406:Receptors, Serotonin, 5-HT3 / Q000235:genetics / Q000378:metabolism*; D013004:Somatostatin / Q000378:metabolism; D000074482:Thyroid Nuclear Factor 1; D014157:Transcription Factors / Q000235:genetics; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D002766:Cholecystokinin; D008164:Luminescent Proteins; D008239:Lysine; D018377:Neurotransmitter Agents; D009687:Nuclear Proteins; D044406:Receptors, Serotonin, 5-HT3; D013004:Somatostatin; D000074482:Thyroid Nuclear Factor 1; D014157:Transcription Factors; D014660:Vasoactive Intestinal Peptide; C499317:Ascl1 protein, mouse; C000614414:Nkx2-1 protein, mouse; C013411:biocytin